KR100248304B1 - Method of forming a layer of pdp - Google Patents

Abstract

The present invention discloses a novel method of forming a fluorescent layer of a PDP.

Transmissive PDPs have high luminance but require a thin and uniform fluorescent layer, and mainly use reflective PDPs.

In the present invention, a fluorescent layer is formed by a printing method to impart a positive photosensitive characteristic, and the thin film layer is formed by limiting exposure and development to realize a thin and uniform fluorescent layer, thereby enabling the practical use of a transmissive PDP.

Description

Method of forming fluorescent layer in plasma display device

1 is a cross-sectional view showing the configuration of a transmissive PDP,

2 is a cross-sectional view showing the configuration of a reflective PDP,

3 (a) to (c) are sequential cross-sectional views showing the method of the present invention,

4 (a) to (d) are sequential cross-sectional views showing another method of the present invention.

Explanation of symbols on the main parts of the drawings

P1, P2: Front and Back Boards

E1, E2: electrode

B: bulkhead

F; R, G, B: fluorescent layer

The present invention relates to the manufacture of a plasma display panel (PDP), and more particularly to a method of forming a fluorescent layer.

PDP is a flat panel display device which applies gas discharge phenomenon to image display, and its basic configuration is the electrodes E1 on two substrates P1 and P2 filled with discharge gas therebetween as shown in FIG. 1 and FIG. , E2) is arranged to face each other and partitioned into partitions B. FIG.

The light generated by the discharge between the two electrodes E1 and E2 is mainly ultraviolet rays, so that the PDP forms a fluorescent layer F which is excited by the ultraviolet rays to generate visible light to increase the luminance of the light or to implement a color image. do.

In this case, the fluorescent layer F may be formed on the front substrate P1 or the rear substrate P2 as shown in FIG. 1, and the transmissive and reflective PDPs may be formed. Call it.

Since the transmissive PDP of FIG. 1 is formed between the partition walls B of the front substrate P1, which is a light transmission path, light generated by the discharge in the discharge space below the light can be transmitted to the front substrate P1 as it is. Although there is an advantage in that the brightness is high, in this case, if the fluorescent layer F is not formed to have a uniform and thin thickness, the fluorescent layer F itself blocks light transmission to lower the luminous efficiency. Thus, the uniform and thin fluorescent layer F is difficult to achieve by a general printing method.

Accordingly, most of the PDP adopts the reflective PDP as shown in Fig. 2. The reflective PDP cannot increase the luminous efficiency unless the surface area of the fluorescent layer F is large. Various means have been devised to form a U-shaped cross section, etc., but all of them have a problem in the method, which is not suitable for mass production of PDP.

In other words, the formation of the fluorescent layer F has been a major obstacle to the mass production of high quality PDPs in any of the transmissive and reflective PDPs.

It is an object of the present invention to provide a method of forming a fluorescent layer suitable for realizing a transmissive PDP, since a fluorescent layer having a uniform and thin thickness can be easily formed in view of such conventional problems.

In order to achieve the above object, the fluorescent layer forming method of the present invention forms a fluorescent layer having positive photosensitivity by a printing method on one surface of a substrate, and then photo-etches the fluorescent layer by limiting exposure on the other surface of the substrate. trimming by etching.

The limited exposure here is a concept that limits the exposure conditions and is distinct from the partial exposure that limits the exposure area.

The fluorescent layer imparts positive photosensitive characteristics at the time of printing or post-printing, so that the printed fluorescent layer can be trimmed to a thin and uniform thickness by photolithography by limited exposure on the other surface of the substrate. It is.

Such specific features and advantages of the present invention will become more apparent from the following description of the preferred embodiments with reference to the accompanying drawings.

In FIG. 3A, one surface of the front substrate P1 on which the substrate E1 is formed (preferably in FIGS. 1 and 2) is a fluorescent layer F; R, G, B) is formed by a general printing method.

When the fluorescent layer F is formed of a color by each of the R, G, and B fluorescent layers, each of the fluorescent layers R, G, and B is sequentially printed to form a pattern (a).

Typical phosphor slurry for the formation of the fluorescent layer (F; R, G, B) has a composition containing the phosphor powder suspended in pure water and containing a small amount of PVA, in the present invention, the fluorescent layer (F Forming a fluorescent layer (F; R, G, B) by incorporating a photosensitive material such as an ADC (Ammonium Di Chloride) or a Di-Azo system into the phosphor slurry in order to impart positive photosensitivity to R, G, and B); Done.

After the fluorescent layer F is sufficiently dried, the substrate P1 burns in FIG. 3 (b), that is, the exposure light source is irradiated from the entire surface of the front substrate P1 to fully cover the fluorescent layer F. Exposure.

At this time, the exposure is performed by limiting the exposure intensity or exposure time appropriately so that the exposure range of the fluorescent layer F reaches the dotted line position.

Then, the portion under the dotted line of the fluorescent layer F does not change the degradability of the photosensitive material by exposure, that is, the degradability of the hardened and unexposed portion does not change.

Next, when the fluorescent layer F is developed by spraying or dipping the washing water, the fluorescent layers F (R; G, B) remain only in the exposed portion as shown in (c).

PVA, photosensitive material, and the like remaining in the fluorescent layers F; R, G, and B are burned and discharged in a subsequent heating process such as high temperature exhaust or a separate firing process, and the fluorescent layers F; R, G and B) are formed to be thin and uniform thickness as shown.

In the embodiment of FIG. 3, the photosensitive material is mixed with the phosphor slurry to print the phosphor layers (F; R, G, and B), and then trimmed by photolithography using limited exposure. As the composition of the slurry changes, many experiments and studies are required to establish proper printing conditions.

Accordingly, in the embodiment shown in FIG. 4, the composition of the phosphor slurry at the time of printing is conventionally used so that the printing methods and conditions established and used in the conventional manner can be applied as they are.

That is, the phosphor layer having the same composition as in the prior art is completed by printing the phosphor layer F or R, G, B phosphor slurry as described in (A) to form the phosphor layer (F; R, G, B).

The fluorescent layer (F; R, G, B) is weakly bonded in a porous state by a molecular force such as van der Waals force of the phosphor itself, in addition to the binding force of a small amount of PVA in the dried state.

Then, the photosensitive material solution is injected from the upper portion of the fluorescent layer (F; R, G, B) by injection, front printing, or immersion, and the like, and the fluorescent layer (F; R, G, B) is added. This photosensitive material solution is impregnated. Here, the aqueous solution of the photosensitive material may be composed of a composition containing a photosensitive material such as ADC or Di-Azo in pure water and, if necessary, a small amount of PVA.

After the impregnation of the photosensitive material on the fluorescent layer F (R; G, B) is completed, the fluorescent layer F is exposed to limited exposure from the back surface of the substrate P1 as shown in (C), and developed by washing or the like. A thin and uniform fluorescent layer (F; R, G, B) is obtained.

As described above, according to the present invention, it is widely used for forming the fluorescent layer (F) of the conventional PDP, while applying the printing method that is familiar with the process and the conditions are optimized, while trimming it by photolithography by limited exposure, it is thin and uniform. The fluorescent layer F (R; G, B) of thickness can be formed.

Furthermore, the method of the present invention can be implemented in addition to or without replacing or changing the conventional printing method, and since the adoption of the method of the present invention does not involve a process or a facility change, a high-quality fluorescent layer with low facility cost and manufacturing labor F) can be manufactured.

Thus, in the present invention, it is possible to form a thin and uniform fluorescent layer F which is almost impossible with the conventional printing method, and in particular, there is a very large effect of enabling the practical use of the transmissive PDP.

Claims (4)

In the method of forming a fluorescent layer on a substrate of a plasma display device, After forming a fluorescent layer having a positive photosensitive characteristics on one surface of the substrate by a printing method, And forming the fluorescent layer by limiting exposure and developing the fluorescent layer on the other surface of the substrate. The method of claim 1, And the fluorescent layer is formed by printing a phosphor slurry mixed with a photosensitive material having the positive photosensitive characteristics. The method of claim 1, After forming the phosphor layer by printing a phosphor slurry, And a photosensitive material having the positive photosensitive property is impregnated into the fluorescent layer. The method of claim 1, The fluorescent layer is composed of a fluorescent layer of R, G, B, And trimming is performed after sequentially printing the R, G, and B fluorescent layers.